With the advent of the mobile internet era, intelligent mobile terminal devices have become gradually essential communication & entertainment tools for people in life, and at work, and on a journey. However, with the growth of entertainment, power consumption of the mobile terminal has increased greatly, such that charging at anytime, anywhere for the mobile terminal device is required. Additionally, with the rapid development of the OTG (On-The-Go) technology, a data processing device between the intelligent mobile terminals in the OTG mode emerges as the times require, However, intelligent mobile terminals which can be connected with the current device are relatively simple, and cannot simultaneously support data transmission between the intelligent mobile terminal and a personal computer (PC). Furthermore, related portable devices only support the universal serial bus (USB) or only support the connection with an interface of a card reader, thus people usually have to carry a variety of charging, data transmission, and storage accessories in the bag to meet different requirements, which bring burden and inconvenience for people. Therefore, it is urgent to develop a multifunctional portable device which can charge for the user at anytime, support a variety of data transmission modes, and connect with multiple intelligent mobile terminals, and support the USB and the interface of the card reader at the same time, thereby reducing the burden of the user's bag and enhancing the user experience.